Clinical Features, Treatment, and Prognosis of Pembrolizumab-Induced Isolated Adrenocorticotropic Hormone Deficiency.

To investigate the clinical characteristics of isolated adrenocorticotropic hormone deficiency (IAD) induced by pembrolizumab, and to provide reference for diagnosis and treatment. Clinical reports of pembrolizumab-induced IAD before February 28, 2025 were collected for retrospective analysis. Twenty (51.3%) women and 19 (48.7%) men entered the study, with a median age of 66 years (range: 38-85). The median time for the onset of IAD was 7.3 months (range: 2-30) after initial administration, and the median cycle was 7 cycles (range: 2-40). Fatigue (65.8%) and anorexia (52.6%) were the most common complaints. Hyponatremia (92.3%) and eosinophilia (33.3%) were the laboratory abnormalities most commonly associated with IAD. Pituitary magnetic resonance imaging (MRI) was normal in most patients (88.2%). After receiving glucocorticoid therapy, patients' symptoms improved significantly with or without pembrolizumab. Pembrolizumab-induced IAD is a rare disease that needs to be paid sufficient attention to. IAD patients have nonspecific manifestations and may be delayed in diagnosis. Further studies are needed to confirm the risk factors and prognosis of pembrolizumab-induced IAD.